Grant Aerona3 Series, Installation And Servicing Instructions

Page: 19 / 88

Section 5: Installation of the Oil Boiler Page 19
If the boiler is to be used without the heat pump fitted, the
heat pump flow and return connections on the boiler MUST be
connected together, as described above, BEFORE the system
and boiler are filled with water.
!
WARNING
5.4.2 ‘Boiler only’ controls
If the boiler is to be used as a ‘stand-alone’ unit, without the heat
pump connected, the ‘Oil/Hybrid’ switch on the Hybrid control panel
(in the boiler) MUST be set to ‘Oil’ for the boiler to operate.
Depending on the hot water controls option fitted, it may be
necessary to alter either the connections to the heating system
controls terminal block (in the hybrid control panel) in the boiler or
change the control settings for the boiler to operate to heat a hot
water cylinder. Refer to Section 11 for details of the hot water control
options and Section 12 for details of the electrical connections.
Figure 5-2: Flow and return connections
3
2
1
6
5
4
Any such changes to connections or settings MUST be
reversed when the heat pump is connected to the boiler and
operation of both together as a hybrid unit is required.
!
WARNING
Table 5-1: Flow and return key
Item Description Item Description
1 System return (1" BSP female) 4 Return (1¼" BSP male)
2 System flow (1" BSP female) 5 Heat pump return (1" BSP female)
3 Flow (1¼" BSP male) 6 Heat pump flow (1" BSP female)